High-performance and linear thin-film lithium niobate Mach-Zehnder modulators on silicon up to 50 GHz.

Compact electro-optical modulators are demonstrated on thin films of lithium niobate on silicon operating up to 50 GHz. The half-wave voltage length product of the high-performance devices is 3.1 V.cm at DC and less than 6.5 V.cm up to 50 GHz. The 3 dB electrical bandwidth is 33 GHz, with an 18 dB extinction ratio. The third-order intermodulation distortion spurious free dynamic range is 97.3 dBHz2/3 at 1 GHz and 92.6 dBHz2/3 at 10 GHz. The performance demonstrated by the thin-film modulators is on par with conventional lithium niobate modulators but with lower drive voltages, smaller device footprints, and potential compatibility for integration with large-scale silicon photonics.

Heterogeneous microring and Mach-Zehnder modulators based on lithium niobate and chalcogenide glasses on silicon.

Thin films of lithium niobate are wafer bonded onto silicon substrates and rib-loaded with a chalcogenide glass, Ge(23)Sb(7)S(70), to demonstrate strongly confined single-mode submicron waveguides, microring modulators, and Mach-Zehnder modulators in the telecom C band. The 200 µm radii microring modulators present 1.2 dB/cm waveguide propagation loss, 1.2 × 10(5) quality factor, 0.4 GHz/V tuning rate, and 13 dB extinction ratio. The 6 mm long Mach-Zehnder modulators have a half-wave voltage-length product of 3.8 V.cm and an extinction ratio of 15 dB. The demonstrated work is a key step towards enabling wafer scale dense on-chip integration of high performance lithium niobate electro-optical devices on silicon for short reach optical interconnects and higher order advanced modulation schemes.

Occupations and the risk of buccal mucosa cancer in Indian men: A multi-centre case-control study.

OBJECTIVE: This study aimed to investigate the association between lifetime occupational history and risk of buccal mucosa cancer (BMC). METHODS: We utilized a multi-centric, hospital-based case-control study across five centres of Tata Memorial Centre, Mumbai, India. Cases included men aged 20-75-years with histological confirmed primary cancer of the buccal mucosa. Visitor controls were frequency matched to cases for age (10 years interval) and current residential zone. Study participants were interviewed face-to-face. Logistic regression was performed to estimate odds ratio (OR) and 95 % confidence intervals (CI). RESULTS: Among ever employed males, we identified 1969 BMC cases and 2145 controls. We observed an increased risk of BMC in 'Craft and Related Trades Workers' (OR 1.37; 95 % CI 1.13-1.65), 'Plant and Machine Operators and Assemblers' (OR: 1.26; 95 % CI 1.01-1.56), and 'Elementary Occupations' (OR:1.33; 95 % CI 1.12-1.58). More specifically, the increased risk was observed for 'Metal, Machinery and Related Trades Workers', 'Handicraft and Printing Workers', 'Drivers and Mobile Plant Operators', and 'Laborers in Mining, Construction, Manufacturing and Transport'. CONCLUSION: Our findings suggest that certain occupations may be at a higher risk of BMC. Some fraction of BMC can be prevented by reducing exposure to hazardous agents used in these occupations. Further research is needed to identify which exposures are responsible for the increased risk. Moreover, tobacco control and early detection activities can be focused towards these occupations as tobacco consumption is also high in them, which may also be the reason for increased risk observed in these groups.

Impact of Serum Amylase Level in the Outcome of Acute Organophosphorus Poisoning: 2-Year Cross-Sectional Study at Rural Teaching Hospital.

Introduction Prompt recognition and aggressive management of acute intoxication due to organophosphorus poisoning are essential to minimize the morbidity and mortality. The present study was undertaken to know the prognosis and outcome of organophosphorus poisoning patients with the estimation of low-cost enzymes like the serum amylase level in a population with financial constraints. Methods In this cross-sectional study, we had enrolled 100 cases that had a history of exposure to organophosphorus compounds, and the serum amylase level was measured in all the patients. We assessed the outcome of all the patients in the form of discharge, need of ventilators, intensive care unit stay, and death. Results The mean serum amylase level in discharge patients was 335.40 ± 192.45, and in the patients who died it was 843.37 ± 22.60. It was significant to predict the outcome ( t -value 7.07, p -value 0.0001, statistically significant). Conclusion Serum amylase level shows significant correlation with clinical outcomes in organophosphorus poisoning.

A comparative study of the clinical efficiency of chemomechanical caries removal using Carie-Care gel for permanent teeth of children of age group of 12-15 years with that of conventional drilling method: A randomized controlled trial.

BACKGROUND: Dental caries is considered as one of the most serious dental diseases that results in localized dissolution and destruction of the calcified tooth tissues. As possible alternatives to conventional techniques of caries removal, chemomechanical caries removal systems have emerged. This study aims to clinically observe the advantages of chemomechanical method of caries removal over conventional technique. MATERIALS AND METHODS: Inthis randomized controlled trial a total of 60 children with Class 1 open carious lesions were selected for the study. They were divided into two equal groups according to a method of caries removal (30 chemomechanical and 30 conventional on permanent molars). In Group A, caries was removed using the Carie-Care system and in Group B with the conventional drill and were restored equally with glass ionomer cement. The visual analogy face scale was used to determine the level of anxiety in children at baseline, during treatment and after treatment. RESULTS: The results were subjected to statistical analysis using Student's unpaired t-test. It showed that though chemomechanical technique took a marginal increase in time compared to the conventional technique, it was found to be more comfortable for all the children. CONCLUSION: Chemomechanical technique though time-consuming is definitely superior compared to the conventional technique provided we use a less technique sensitive restorative material which retains in the oral cavity for longer period. It is definitely a better treatment protocol in school-based dental treatment and atraumatic restorative dentistry compared to the conventional technique.

Optimizing effectivity of tranexamic acid in bilateral knee arthroplasty - A prospective randomized controlled study.

INTRODUCTION: Tranexamic acid (TEA) is used in reducing surgical blood loss. Literature shows no optimal regimen recommended for Bilateral Total Knee Arthroplasty (TKA). We evaluated three TEA regimens differing in dosage, timing and mode of administration in bilateral TKA to identify the most effective regimen to reduce blood loss. METHODS: We prospectively studied three TEA regimens (25 patients each) as follows: (1) two intraoperative, intravenous doses (IOIO), (2) two intraoperative local applications (LALA), and (3) one preoperative plus two intraoperative, intravenous doses (POIOIO). Two independent parameters of drain loss and total blood loss, calculated by the hemoglobin balance method were statistically evaluated. RESULTS: Mean drain loss was least (412.9ml) in the POIOIO group, greatest (607.2ml) in the IOIO group and LALA group in between (579.4ml), with a statistically significant difference among them (p=0.0022). On paired evaluation, the drain loss in the POIOIO group was significantly less as compared to the other two groups, whereas the difference between IOIO and LALA was not significant. Mean total blood loss was least in the POIOIO group (1207ml) and greatest in LALA group (1270ml). The difference among the groups was not statistically significant (p=0.80). There was no incidence of any thromboembolic phenomenon. On correlation with our study on Most Effective Regimen in Unilateral TKA, both results were found to substantiate each other.

Effect of Preoperative Vitamin D Levels on Functional Performance after Total Knee Arthroplasty.

BACKGROUND: Low vitamin D levels affects muscle function. Vitamin D and calcium deficiency cause osteomalacic myopathy and poor functional recovery after hip fractures. The relationship of vitamin D and functional performance after total knee arthroplasty (TKA) is not previously reported. METHODS: Influence of vitamin D on functional performance before and after TKA was reviewed retrospectively in 120 patients. Of these, 64 had vitamin D deficiency (25-hydroxy vitamin D < 30 ng/mL) preoperatively. All 120 patients received vitamin D oral supplementation postoperatively. Functional parameters including Western Ontario and McMaster Osteoarthritis Index (WOMAC), Short-Form Health Survey questionnaire, and Knee Society Score were assessed pre- and postoperatively at 3 months. RESULTS: Preoperative function was significantly lower in osteoarthritic patients with vitamin D deficiency (WOMAC score; p = 0.040), but at 3 months all functional scores were similar. CONCLUSIONS: We concluded that vitamin D deficiency has a negative effect on function in knee osteoarthritic patients. However, postoperative vitamin D supplementation can lead to functional recovery in these patients. Thus, TKA should not be delayed in vitamin D deficient patients; rather supplementation in the postoperative period is preferable to achieve comparable functional outcome at 3 months to patients with vitamin D sufficiency.

Carpometacarpal Joint Fracture Dislocation of Second to Fifth Finger.

BACKGROUND: Carpometacarpal joint fracture dislocation of the second to fifth finger is a rare hand injury associated with high energy trauma. Due to severe swelling and overlapping of bones on the radiograph of wrist-hand, dislocations are missed. We reported a series of six patients with rare carpometacarpal joint fracture dislocation treated with open reduction. METHODS: We retrospectively studied six cases of carpometacarpal joint fracture dislocation. All patients were treated with open reduction and internal fixation with Kirschner wire. Functional assessment was done with Quick Disabilities of the Arm, Shoulder and Hand score (Quick DASH score) at regular intervals. RESULTS: Average Quick DASH score was improved from 75.76 to 1.9 from 6 weeks to 18 months of duration. Of the six patients, three patients had a Quick DASH score of 0 at the end of 18 months. CONCLUSIONS: Careful hand examination and radiographic assessment is necessary to avoid missed diagnosis of carpometacarpal joint fracture dislocation. Early open reduction and internal fixation lead to excellent recovery of hand function.

Mid term results of LCS knee: The Indian experience.

BACKGROUND: The low contact stress rotating platform (LCS RP) knee (DePuy Orthopedics, Inc, Warsaw, Indiana), in use for last four decades in Western population, is reported to have a survival of more than 95% at 15 to 20 years. The reported Indian experience of this knee is limited to 5 years. Our aim was to report the clinical and radiological results of the LCS RP TKA design in the Indian population with a minimum followup of 10 years. MATERIALS AND METHODS: Fifty-five LCS knees (45 patients) operated between February 1997 and October 2001 were evaluated retrospectively. LCS design was generally selected if the patient was young (≤65 years of age), active and had no severe deformity. There were 40 female (88.9%) and 5 male (11.1%) patients; 47 knees had osteoarthritis (85.5%) and 8 knees had rheumatoid arthritis (14.5%). Knee Society Scores (KSS) and outcome questionnaire were filled at followup and radiographs were analyzed using Knee Society radiographic evaluation and scoring system. RESULTS: Of 45 patients (55 knees) enrolled, 37 patients (44 knees; 80%) were available for followup at 10 years. Average age was 59.6 years (range 40 to 77). Minimum followup was 10 years (average 12.3 years; range 10 to 15.3 years.). Three knees (6.8%) had been revised, one each for aseptic loosening, bearing dislocation and infection. Mean preoperative KSS of 33 improved to 91 postoperatively. Mean preoperative functional score of 45 improved to 76 postoperatively. Mean preoperative flexion of 113° (90°-140°) reduced to 102° (80°-135°) postoperatively. Erratic femoral rollback and tighter flexion gap to prevent spin out are the probable factors for decreased postoperative range of motion. Five (12%) patients could sit cross-legged and sit on the floor. Anterior knee pain was present in 4.6% (2/44 knees). The survival was 93.2% at 12.3 years. One patient (1.8%) had spin-out of the rotating bearing. No knee had osteolysis or progressive radiolucent lines on X-rays. CONCLUSION: LCS implant has given good survival (93.2% at 12.3 years) with low rates of spin-out and anterior knee pain and no incidence of osteolysis. Limited flexion post surgery (104°) with only 12% managing to sit cross legged on the floor is a drawback.